Optimal First-Line Medico-Surgical Strategy in Ovarian Cancers: Are We There Yet?

In spite of tremendous advances in advanced ovarian cancer management through the past decade, notably owing to surgical expertise and novel combination molecules (including bevacizumab and PARP inhibitors), the optimal initial sequential strategy remains a major concern. Indeed, following seminal clinical trials, primary cytoreductive surgery (PCS) followed by adjuvant systemic therapy and interval cytoreductive surgery (ICS) following neoadjuvant chemotherapy (NACT) have been positioned as validated alternatives with distinct pros and cons, although a definite response is still unassessed. In clinical practice, decisions between PCS and ICS rely on multilayer parameters: the tumor itself, the patient, and the health structure. In this state-of-the-art review, we will discuss the current evidence based on clinical trials and real-world data and highlight the remaining questions, including the fittest positioning of PCS vs. ICS and the optimal number of NACT cycles; subsequently, we will discuss current axes of research such as dedicated clinical trials and more global perspectives. These ongoing strategies and perspectives could contribute to improving the patient journey through personalized medicine.

Optimal timing of interval debulking surgery for advanced epithelial ovarian cancer: A retrospective study from the ESME national cohort

OBJECTIVE

Interval debulking surgery is recommended after 3-4 cycles (standard IDS) of neoadjuvant chemotherapy (NACT) for epithelial ovarian cancer (EOC) not able to received upfront complete debulking surgery. However, real world practices frequently report performing IDS after ≥5 NAC cycles (delayed IDS). The aim of this work was to evaluate the impact on survival of the number of NACT cycles before IDS.

METHODS

We identified from a French national database, women with newly diagnosed EOC who underwent IDS from January 2011 to December 2016. Progression free survival (PFS) and overall survival (OS) were compared using Cox model with adjustments for confounding factors provided by two propensity score methods: inverse probability of treatment weighting (IPTW) and matched-pair analysis.

RESULTS

928 patients treated by IDS for which our propensity score could be applied were identified. After a median follow-up of 49.0 months (95% CI [46.0;52.9]); from the IPTW analysis, median PFS was 17.6 months and 11.5 months (HR = 1.42; CI 95% [1.22-1.67]; p < 0.0001); median OS was 51.2 months and 44.3 months (HR = 1.29; CI 95% [1.06-1.56]; p = 0.0095) for the standard and delayed IDS groups. From the matched-pair analysis (comparing 352 patients for each group), standard IDS was associated with better PFS (HR = 0,77; CI 95% [0.65-0.90]; p = 0.018) but not significantly associated with better OS (HR = 0,84; CI 95% [0.68-1,03]; p = 0.0947).

CONCLUSIONS

Carrying IDS after ≥5 NACT cycles seems to have a negative effect on patients survival. The goal of IDS surgery is complete resection and should not be performed after >3-4 NACT cycles.

The Increasing Prognostic and Predictive Roles of the Tumor Primary Chemosensitivity Assessed by CA-125 Elimination Rate Constant K (KELIM) in Ovarian Cancer: A Narrative Review

Ovarian cancer is the gynecological cancer with the worst prognosis and the highest mortality rate because 75% of patients are diagnosed with advanced stage III-IV disease. About 50% of patients are now treated with neoadjuvant chemotherapy followed by interval debulking surgery (IDS). In that context, there is a need for accurate predictors of tumor primary chemosensitivity, as it may impact the feasibility of subsequent IDS. Across seven studies with more than 12,000 patients, including six large randomized clinical trials and a national cancer registry, along with a mega-analysis database with 5842 patients, the modeled CA-125 ELIMination rate constant K (KELIM), the calculation of which is based on the longitudinal kinetics during the first three cycles of platinum-based chemotherapy, was shown to be a reproducible indicator of tumor intrinsic chemosensitivity. Indeed, KELIM is strongly associated with the likelihood of complete IDS, subsequent platinum-free interval, progression-free survival, and overall survival, along with the efficacy of maintenance treatment with bevacizumab or veliparib. As a consequence, KELIM might be used to guide more subtly the medical and surgical treatments in a first-line setting. Moreover, it could be used to identify the patients with poorly chemosensitive disease, who will be the best candidates for innovative treatments meant to reverse the chemoresistance, such as cell cycle inhibitors or immunotherapy.

The role of the tumor primary chemosensitivity relative to the success of the medical-surgical management in patients with advanced ovarian carcinomas

In patients with advanced ovarian carcinomas, the first-line treatment has historically relied on debulking surgery and platinum-based chemotherapy. If the major therapeutic/prognostic role of the surgery part is well understood, and integrated in disease-management algorithms, the impact of chemotherapy efficacy has been insufficiently addressed. This review describes the main indicators of the chemosensitivity reported in the literature (pathological response score & biomarkers; genomic alterations; DNA scars; imaging; and circulating tumor markers), and investigates the respective roles of the debulking surgery and tumor primary chemosensitivity relative to the success of the comprehensive medical-surgical treatment. The tumor primary chemosensitivity exhibits a major independent prognostic impact on the feasibility of complete interval debulking surgery after neoadjuvant chemotherapy, risk of subsequent platinum-resistant relapse, efficacy of subsequent maintenance therapies with bevacizumab or PARP inhibitors, progression-free survival, overall and long-term survival. While both the completeness of the surgery and the tumor primary chemosensitivity are undoubtedly major prognostic factors, the impact of the surgery may differ according to the primary chemosensitivity. This assumption raises a potential new concept: in patients with advanced ovarian carcinomas, the maximum tumor debulking should ideally be both biological (induced by systemic treatments) and physical (induced by surgery) for maximizing patient survival. Besides BRCA and HRD biomarkers, future trials and algorithms may integrate indicator(s) of the tumor primary chemosensitivity for guiding more subtly the surgical and medical management in first-line setting. Moreover, such a parameter would help in the development of novel approaches meant to reverse the resistance to chemotherapy and PARP inhibitors.

CA-125 ELIMination Rate Constant K (KELIM) Is a Marker of Chemosensitivity in Patients with Ovarian Cancer: Results from the Phase II CHIVA Trial

PURPOSE

In patients with ovarian cancer receiving neoadjuvant chemotherapy, the first-line treatment success will depend on both the tumor-primary chemosensitivity and the completeness of interval debulking surgery (IDS). The modeled CA-125 ELIMination rate constant K (KELIM), calculated with the CA-125 longitudinal kinetics during the first 100 chemotherapy days, is a validated early marker of tumor chemosensitivity. The objective was to investigate the role of the chemosensitivity relative to the success of first-line medical-surgical treatment.

EXPERIMENTAL DESIGN

The CA-125 concentrations were prospectively measured in the randomized phase II trial CHIVA (NCT01583322, carboplatin-paclitaxel regimen ± nintedanib, and IDS, n = 188 patients). The KELIM predictive value regarding the tumor response rate, likelihood of complete IDS, risk of subsequent platinum-resistant relapse (PtRR), progression-free survival (PFS), and overall survival (OS) was assessed using univariate and multivariate tests.

RESULTS

The data from 134 patients were analyzed. KELIM was an independent and major predictor of subsequent PtRR risk, and of survivals. The final logistic regression model, including KELIM [OR = 0.13; 95% confidence interval (CI), 0.03-0.49] and complete IDS (no vs. yes, OR = 0.30; 95% CI, 0.11-0.76) highlights the preponderant role of chemosensitivity on the success of the first-line treatment. In patients with highly chemosensitive diseases, the patient prognosis was driven more by the chemotherapy-induced antitumor effects than by the surgery.

CONCLUSIONS

The tumor-primary chemosensitivity, assessed by the modeled CA-125 KELIM calculated during neoadjuvant chemotherapy (http://www.biomarker-kinetics.org/CA-125-neo), may be a major parameter to consider for decision-making regarding IDS attempt, and selecting patients for treatments meant to reverse the primary chemoresistance.See related commentary by May and Oza, p. 4432.